Experiments suggest hop compounds fight cancer

03/13/1998

CORVALLIS, Ore. - Can drinking beer help you fight cancer?

Oregon State University scientists are a long way from saying that. But they have done studies with mouse and human cells in which compounds in hops, cone-shaped flowers used to flavor and preserve beer, seemed to work against the disease. The compounds are called flavonoids.

The researchers reported their findings recently in Seattle at the annual meeting of the international Society of Toxicology.

"We knew flavonoids from other plants had these types of effects so we decided to test hops flavonoids for anti-cancer activity," said Donald Buhler, an agricultural chemist with the university's Agricultural Experiment Station.

"We treated human breast, colon and ovarian cells that were cancerous with concentrations (of flavonoids) that were not harmful to normal cells and found that some of the hops flavonoids were toxic to cancer cells," said Buhler.

The substance in the hops flavonoids most toxic to cancer cells is named xanthohumol, the researcher said.

The OSU research team conducted two related experiments. In one experiment, some flavonoids in hops helped inhibit an enzyme - commonly called cytochrome P450 - that can activate the cancer process.

In another experiment, some of the flavonoids helped enhance the impact of a class of enzymes, called quinone reductase, that can detoxify cancer-causing substances that have been activated.

"It's a little early in the game to start jumping to conclusions," said Buhler. "We're planning additional studies with mice that could provide more telling results."

However, the researcher said the hop flavonoids are in beer. The level depends partly on the brewing process used.

"I wouldn't encourage people to drink more," he said. "Obviously there's a down side to drinking. But these results are really interesting. If these things really prove to be beneficial it might be possible to find a way to get them to people in capsules or some other concentrated form."

Organizations funding the research included the Hop Research Council, the Medical Research Foundation of Oregon, the National Institute of Environmental Health Sciences, the U.S. Department of Agriculture and OSU's Environmental Health Sciences Center.

Members of the OSU research team, besides Buhler, are: Max Deinzer, Rosita Rodriguez, Cristobal Miranda, Fred Stevens, Marilyn Henderson, Lalith Aponoso and Angela Sharps. The researchers are from OSU's departments of Agricultural Chemistry, Biochemistry and Biophysics, Chemistry, and from the university's College of Pharmacy.